A retrospective evaluation of the pulmonary function tests and quality of life assessment surveys of emphysema patients subject to coil treatment
doi • 10.5578/tt.70358
Tuberk Toraks 2020;68(4):399-406
Geliş Tarihi/Received: 15.05.2020 • Kabul Ediliş Tarihi/Accepted: 29.12.2020
KLİNİK ÇALIŞMA RESEARCH ARTICLE
Erhan UĞURLU1(ID) Nazlı ÇETİN1(ID) Nilüfer YİĞİT1(ID) Ümit AYDOĞMUŞ2(ID) İlknur Hatice
AKBUDAK3(ID) Hande ŞENOL4(ID) Fikri Selçuk ŞİMŞEK5(ID) Göksel ALTINIŞIK1(ID)
1 Department of Chest Diseases, Pamukkale University School of Medicine, Denizli, Turkey
1 Pamukkale Üniversitesi Tıp Fakültesi, Göğüs Hastalıkları Anabilim Dalı, Denizli, Türkiye
2 Department of Thoracic Surgery, Pamukkale University School of Medicine, Denizli, Turkey
2 Pamukkale Üniversitesi Tıp Fakültesi, Göğüs Cerrahisi Anabilim Dalı, Denizli, Türkiye
3 Department of Anesthesia and Reanimation Pamukkale University School of Medicine, Denizli, Turkey
3 Pamukkale Üniversitesi Tıp Fakültesi, Anestezi ve Reanimasyon Anabilim Dalı, Denizli, Türkiye
4 Department of Biostatistics, Pamukkale University School of Medicine, Denizli, Turkey
4 Pamukkale Üniversitesi Tıp Fakültesi, Biyoistatistik Anabilim Dalı, Denizli, Türkiye
5 Department of Nuclear Medicine, Pamukkale University School of Medicine, Denizli, Turkey
5 Pamukkale Üniversitesi Tıp Fakültesi, Nükleer Tıp Anabilim Dalı, Denizli, Türkiye
ABSTRACT
A retrospective evaluation of the pulmonary function tests and quality of life assessment surveys of emphysema patients subject to coil treatment Introduction: Bronchoscopic volume reduction treatments are among the important alternatives for selected emphysema patients with a dyspneic cour- se despite optimal medical treatment. Our aim was to carry out a retrospecti- ve scan of the data for COPD patients subject to coil treatment at our center for assessing whether coil procedure has an impact on the respiratory symptom and pulmonary function tests in COPD patients.
Materials and Methods: The data of 41 patients with severe emphysema and treated with coils between 2017-2020 were evaluated retrospectively.
Cardiopulmonary rehabilitation programs were completed for all patients Dr. Ümit AyDoğMUş
Pamukkale Üniversitesi Tıp Fakültesi, Göğüs Cerrahisi Anabilim Dalı, DENİZLİ - TÜRKİyE
e-mail: mdaydogmus@yahoo.com
Yazışma Adresi (Address for Correspondence) Cite this article as: Uğurlu E, Çetin N, Yiğit N, Aydoğmuş Ü, Akbudak İH, Şenol H, et al. A retrospective evaluation of the pulmonary function tests and quality of life assess- ment surveys of emphysema patients subject to coil treatment. Tuberk Toraks 2020;68(4):399-406.
©Copyright 2020 by Tuberculosis and Thorax.
Available on-line at www.tuberktoraks.org.com
INTRODUCTION
Chronic obstructive pulmonary disease (CoPD) is a widespread, preventable and treatable disease char- acterized by respiratory symptoms and permanent air flow restriction, related generally to severe exposure to harmful particles or gases and/or alveolar anoma- lies (1). Emphysema, an important component of CoPD, is characterized by chronic inflammatory structural changes and permanent parenchymal dam- age in the lungs. This leads to dynamic hyperinflation, elastic recoil loss, air trapping resulting in reduced exercise capacity, shortness of breath, and an increased risk for mortality (2).
Quitting smoking, bronchodilator treatments, pulmo- nary rehabilitation, oxygen support, immunization programs, and required nutritional support are among the primary treatment options for CoPD (3). However, the benefits of all these treatment options are limited
in patients whose CoPD is accompanied by emphy- sema since the actual pathology in emphysema is hyperinflation due to elastic-tissue damage.
Bronchoscopic lung volume reduction treatments are among the important alternatives for selected emphy- sema patients with a dyspneic course despite optimal medical treatment (1). Several studies have reported that lung volume reduction procedures increase lung and respiratory muscle function, exercise perfor- mance, quality of life and survival in CoPD patients with emphysema selected in accordance with criteria and that better clinical and functional results are attained particularly in patients with upper lobe pre- dominant emphysema and those with low exercise capacity (4).
Lung parenchyma with abnormal elastic recoil can be contracted, thereby reducing the volume via smart-coil treatment, which is one of the volume prior to the procedure and they were assessed with pulmonary function test (PFT), diffusing capacity for carbonmonoxide test (DLCO), body plethysmography, 6-minute walk test, ventilation/perfusion scintigraphy, St. George’s Respiratory Questionnaire (SGRQ). Data acquired prior to the procedure and 3rd month control data after the procedure were recorded and SGRQ was app- lied via face-to-face interviews during the controls by doctors working on Pulmonary Diseases as was the case before the procedure.
Results: SGRQ questionnaires of 32 patients were evaluated. Statistically significant changes were observed after the procedure in symptom, activity, impact score and total score which were calculated prior to the procedure. Pre and post procedure FEV1, FVC, FEV1/FVC, PEF, FEF25/75 parameters were used for the comparison made via SFT. Statistically significant changes were observed in FEV1, FVC, FEF25/75 when the pre and post-procedure SFT parameters of the 32 patients included in the study were compared.
Conclusion: A statistically significant improvement was observed in the PFT parameters and quality of life questionnaires following the coil procedure which is a bronchoscopic volume reduction procedure.
Key words: D-Coil; emphysema; lung volume reduction; bronchoscopic volume reduction; SGRQ (St. George's Respiratory Questionnaire)
ÖZ
Coil tedavisi yapılmış olan amfizem hastalarının solunum fonksiyon testlerinin ve yaşam kalitesi değerlendirme anketlerinin retrospektif olarak incelenmesi
Giriş: Optimal medikal tedaviye rağmen dispneik seyreden seçilmiş amfizem hastalarında bronkoskopik volüm küçültme tedavileri önemli bir alternatiftir. Merkezimizde coil işlemi yapılan KOAH’lı hastaların geriye dönük takip verilerini tarayarak, coil işleminin KOAH’lı hastalarda solunumsal semptom ve solunum fonksiyon testlerine etkisi olup olmadığını değerlendirmeyi amaçladık.
Materyal ve Metod: 2017-2020 yılları arasında şiddetli amfizemi olan, coillerle tedavi edilen 41 hastanın verileri retrospektif olarak değerlendirildi. İşlem öncesi bütün hastaların kardiyopulmoner rehabilitasyon programları tamamlanmış, hastalar solunum fonksiyon testi (SFT), karbonmonoksit difüzyon testi (DLCO), vücut pletismografisi (body box), 6 dakika yürüme testi, ventilasyon/perfüzyon sintigrafisi, St. George Solunum Anketi (St. George’s Respiratory Questionnaire, SGRQ) ile değerlendirilmiştir. İşlem öncesi ve işlem sonrası 3. ay kontrol verileri kaydedilmiş, işlem öncesi olduğu gibi kontrollerde de SGRQ anketi Göğüs Hastalıkları’nda çalışmakta olan doktorlar tarafından yüz yüze görüşülerek yapılmıştır.
Bulgular: Toplam 32 hastanın SGRQ anketleri değerlendirildi. İşlem öncesi hesaplanan semptom, aktivite, etki (impact) skoru ve toplam skorda işlem sonrası istatistiksel olarak anlamlı değişiklik gözlendi. SFT ile yapılan karşılaştırmada işlem öncesi ve sonrası FEV1, FVC, FEV1/FVC, PEF, FEF25/75 parametreleri kullanıldı. Çalışmaya dahil edilen 32 hastanın işlem öncesi ve sonrası SFT parametreleri karşılaştırıldığında FEV1, FVC, FEF25/75‘te istatistiksel olarak anlamlı değişiklik gözlendi.
Sonuç: Bronkoskopik volüm küçültücü bir işlem olan coil işleminin sonrasında solunum fonksiyon parametrelerinde ve yaşam kalite- si anketlerinde anlamlı bir düzelme olduğu saptanmıştır.
Anahtar kelimeler: Coil; amfizem; akciğer volüm küçültme; bronkoskopik volüm küçültme; SGRQ (St. George's Respiratory Questionnaire)
reduction procedures (5). A literature survey showed that, although there are studies reporting recovery following coil treatment in CoPD patients based on the 6-minute walk test, pulmonary-function test (PFT) parameters, and dyspnea assessment scales, the num- ber of related studies remains limited in our country (6).
Our aim was to conduct a retrospective scan of the data for CoPD patients subjected to coil treatment at our center in order to assess whether the coil proce- dure has an impact on the respiratory symptom and pulmonary function tests in patient with CoPD.
MATERIALS and METHODS Patient Selection
A total of 41 patients were included in the study who underwent the coil procedure and were monitored at our Pulmonary Diseases clinic; all had been diag-
nosed with stage 3 or stage 4 CoPD based on the Global Initiative for Chronic obstructive Lung Disease (GoLD) diagnostic criteria (1), with emphy- sema detected by high-resolution computerized tomography. They were considered eligible for coil treatment and underwent the procedure during october 2017 and February 2020. In all, 32 patients were included in the study because 1 patient was re-coil, 2 patients died during follow-up (myocardial infarction, pneumonitis), and 6 patients did not come for the follow-up. Figure 1 presents a flow diagram of subjects included in this analysis. Table 1 presents the inclusion and exclusion criteria for the patient samples (4).
Cardiopulmonary rehabilitation programs were com- pleted for all patients prior to the procedure and they were assessed with PFT, diffusing capacity for car- bonmonoxide test (DLCo), body plethysmography, the 6-minute walk test, ventilation/perfusion scintig-
Figure 1. Flow diagram.
Patients who were treated at our center between November 2017 and February 2020
Excluded patient (n= 9) -Recoil (n= 1)
-Exitus (n= 2) (myocardial infarction, pneumonia)
-Not available for follow up (n= 6)
Included patient n= 32
Received bilateral coil treatment (n= 19)
Received unilateral coil treatment (n= 13) n= 41
raphy, and St. George’s Respiratory Questionnaire (SGRQ). The included PFT were as forced expiratory volume in the first second (FEV1), forced vital capac- ity (FVC), forced expiratory flow 25-75% (FEF25-75), peak expiratory flow (PEF), residual volume (RV), and total lung capacity (TLC). Data were collected prior to the procedure and again as third month control data after the procedure was recorded, and SGRQ was applied via face-to-face interviews during the controls by doctors treating pulmonary diseases as was the case before the procedure.
Procedure
Coil (PneumRx, Inc., Mountain View, Calif., USA) application:
The procedure was conducted under general anes- thesia at the surgery department and aided by fluo- roscopy. First, the airway in the selected segment is determined bronchoscopically, and its length is mea- sured using a guide wire. A coil of suitable length (generally 100 mm, 125 mm or 150 mm) is then placed on the targeted segment using a carrier cath- eter and takes on the shape of a coil. The airway contracts as the coil pulls on the lobe, and the lungs collapse and shrink. The targeted lobe is systemati- cally treated with 10-14 coils, on average. While a single lobe is treated initially, the other targeted lobe in the opposite lung is treated 4-8 weeks later (4). A postero-anterior chest x-ray of the patient with the bilateral coil procedure is shown in Figure 2.
Tools of Measurement
• Pulmonary function test
• Diffusing capacity for carbon monoxide test
• Body plethysmography
• 6-minute walk test
• Ventilation/perfusion scintigraphy
• SGRQ: A specific questionnaire for respiratory diseases (7), SGRQ examines 50 factors of patients in three classifications: symptoms (8 items), activities (16 items), and effects of the disease (26 items). The response has an empirical weight in all items. Respiratory disorder in the patient, along with cough, phlegm, wheezing, and the level of shortness of breath, are exam- ined when observing the symptoms. The activity score is related to physical activities that may lead to shortness of breath or those that are lim- ited by shortness of breath, whereas the impact score comprises factors such as profession, occupation, managing one’s health, panic, med- ication and its side effects, and discomfort Table 1. Patient inclusion and exclusion criteria
Inclusion Criteria
• Patients undergoing optimal medical treatment (quitting smoking, maximum pharmacological treatment, pulmonary rehabilitation)
• GoLD Stage 3 or 4
• CAT score ≥ 10, mMRC ≥ 2
• FEV1 20-45 %
• RV expected ≥ %175 or RV/TLC ≥ %58
• 6-minute walk test 100-500 m
Exclusion Criteria
• Severe PHT (sPAP >50 mmHg in ECo)
• Clinically severe bronchiectasis
• Suspected pulmonary module
• Diagnosed lung cancer or suspicion
• Interstitial fibrosis
• Severe tracheobronchomalacia
* GoLD: Global initiative for chronic obstructive lung disease; CAT: CoPD assessment test; mMRC: Modified medical research council dys- pnea scale; FEV1: Forced expiratory volume in first second; RV: Residual volume; TLC: Total lung capacity; PHT: Pulmonary hypertension; sPAP:
Systolic pulmonary arterial pressure; ECo: Echocardiography.
Figure 2. Postero-anterior chest X-ray of the patient after bilat- eral coil procedure.
during daily activities of living. The three sec- tions of the questionnaire are scored separately, after which the total score is calculated. The scores range from 0-100, with zero indicating normal function and 100 indicating the most severe symptoms. A four-point change in SGRQ due to treatment is considered statistically signif- icant (8).
Statistical Evaluation
All statistical analyses were performed using SPSS 25.0 software (IBM SPSS Statistics 25 (Armonk, Ny:
IBM Corp.). Continuous data were reported as mean
± standard deviation, whereas the categorical vari- ables were presented in numbers and percentages.
The Shapiro-Wilk test was used for testing normality.
Regarding pairwise comparisons, paired samples t-test was used if the parametric test conditions were satisfied and Wilcoxon signed rank test if not. A p value <0.05 was considered statistically significant.
RESULTS
All 32 patients included in the study were male and, the mean age was 66.13. Comorbidities were benign prostatic hyperplasia in 10 patients (31.25%), hyper- tension in 8 patients (25%), cardiovascular disease in 7 patients (21.87%), and diabetes in 4 patients (12.5%), respectively. Table 2 presents the sociode- mographic data for the patients included in the study.
SGRQ was used to assess 16 patients following uni- lateral coil procedure for control data, and 16 patients were subjected to the control questionnaire following the bilateral coil procedure, for a total of 32 patients. Statistically significant changes were observed following the procedure, and these were assessed by symptom, activity, impact score, and total score, which were also calculated prior to the procedure (Table 3).
Pre- and post- procedure FEV1, FVC, FEV1/FVC, PEF, FEF25-75 parameters were used for the comparison
Table 2. Sociodemographic characteristics and some clinical parameters
Number (n) Percentage (%)
Gender Female Male
0 32
0 100 Comorbidities
Benign prostatic hyperplasia Hypertension
Cardiovascular disease Diabetes
10 8 7 4
31.25 25 21.87
12.5 Procedure
Unilateral Bilateral
13 19
40.62 59.38 Emphysema distribution
Homogeneous Heterogeneous
14 18
43.75 56.25 GoLD spirometric stage
Stage 3 Stage 4
13 19
40.62 59.38 LToT use
Yes No
9 23
28.12 71.88
Mean ± SD Median (min-max)
Age 66.13 ± 6.47 67.5 (49-76)
Used coil (qty.) 15.44 ± 5.41 16 (6-24)
6 MWT 256.52 ± 128.18 210 (100-495)
* GoLD: Global initiative for chronic obstructive lung disease, LToT: Long-term oxygen therapy; 6 MWT: Six minute walk test; SD: Standard devi- ation; min-max: Minimum-maximum values.
made with PFT. Statistically significant changes were observed in FEV1, FVC, FEF25-75 when the pre- and post-procedure PFT parameters of the 32 patients included in the study were compared (Table 4).
Ventilation/perfusion scintigraphy scans could be obtained for only 11 patients subject to bilateral coil procedure. A statistically significant difference could not be observed when the pre- and post-procedure data were compared.
Major shortcomings were observed, especially in the control data on DLCo, body plethysmography, and the 6-minute walk test due to the diagnosis of advanced CoPD in this patient population. In addi- tion, the number of patients was not sufficient for assessment (n <10).
one patient developed a pneumothorax as a compli- cation following the procedure, after which the patient returned to normal with tube drainage. Two patients died in the first month post-procedure, one due to myocardial infarction and one due to pneu- monitis.
DISCUSSION
A positive and statistically significant change was determined in our study in all items of the volumeaire when the SGRQ results were compared before and
after the coil procedure. Statistically significant changes were observed in the PFT parameters of FVC, FEV1 and FEF25-75 before and after the proce- dure. The findings other than those for FEF25-75 were in accordance with the literature (2,3,9). Based on our literature survey, there are no studies that exam- ine the FEF25-75 parameter. Studies have generally focused on PFT parameters of FVC, FEV1, RV, TLC.
Because the real problem in emphysema is hyperin- flation, there is an increase in RV that reduces thorac- ic-wall compliance, thereby making it more difficult to breathe (10). Improvements are expected primarily in RV, as well as in other volumes and capacities after the coil procedure. Hence, these parameters were examined in these studies; however, peripheral air- ways are among the first areas affected by CoPD, and FEF25-75 is one of the parameters that best pres- ents the changes in peripheral airways (11). Since elastic recoil is reduced in emphysema, alveoli and small air-ways collapse during expiration and FEF25-
75 is low; thus an increase is expected in FEF25-75 since elastic recoil improves following the coil pro- cedure.
In our study, the effects of coil therapy on respiratory function tests and the SGRQ in the short term were examined. A future research aim is to study the long- term effects and surveillance of these patients in the Table 4. Pulmonary function test (PFT) comparison
n= 32 Before the procedure
(Mean ± SD) After the procedure
(Mean ± SD) p
FVC 54.47 ± 14.19 61.27 ± 15.03 0.002 α
FEV1 29.12 ± 9.57 33.96 ± 12.44 0.001 β
FEV1/FVC 42.27 ± 8.94 42.42 ± 7.9 0.355 β
PEF 32.12 ± 10.1 42.42 ± 7.9 0.798 α
FEF25-75 11.28 ± 3.83 13.06 ± 5.13 0.007 α
*FVC: Forced vital capacity; FEV1: Forced expiratory volume in first second; PEF: Peak expiratory flow; FEF25-75: Forced expiratory flow %25-75;
SD: Standard deviation; p< 0.05 statistically significant; α: Paired Samples t test; β: Wilcoxon signed rank test.
Table 3. St. George respiratory questionnaire (SGRQ) comparison
n= 32 Before the procedure
(Mean ± SD) After the procedure
(Mean ± SD) p
Symptom score 68.15 ± 19.47 58.27 ± 17.24 0.007 α
Activity score 83.59 ± 17.67 71.22 ± 19.52 0.001 β
Impact score 62.74 ± 22.28 46.23 ± 19.54 0.0001 α
Total score 70.09 ± 18.26 55.97 ± 15.75 0.0001 α
* SD: Standard deviation; p< 0.05 statistically significant; α: Paired Samples t test; β: Wilcoxon Signed Rank Test.
future. As a matter of fact, according to the results of the RESET study where the 5-year surveillance of coil therapy was examined, those who were eligible for coils were found to have improved in terms of sur- veillance compared to those who received standard care (12).
To the best of our knowledge, the number of studies on the coil procedure is limited in our country (13- 19). Similar findings related to PFT were determined when these studies were compared with the findings of the present study. The SGRQ was used only in the study by Gulsen (18). Even though the SGRQ findings were similar in our results, this study focused only on the total score when evaluating the SGRQ findings, whereas the symptom scores, activity scores, and impacts of the disease were evaluated separately in our study and all determined to be statistically signif- icant. In the study conducted by Franke et al., signif- icant changes were found in all three parameters in the pre-coil and post-coil comparison, similar to our study (20). Significant changes were found in the SGRQ in the study in which Fellrath et al. shared the results of assessment 6 months after coil treatment in patients with severe emphysema (21). In the study conducted by Bostancı et al., SGRQ was not includ- ed, but the Medical Research Council scale and Chronic obstructive Pulmonary Disease assessment test were, and significant changes were observed after coil treatment (14). In the same study, a signifi- cant decrease was found in depression and anxiety scores after coil treatment.
No statistically significant change could be observed in either ventilation or perfusion when the targeted lobes (subjected to the lung volume reduction proce- dure) were evaluated during the ventilation/perfusion scintigraphy scans before and after the procedure in our study. It is expected that, after the volume reduc- tion procedure, perfusion and ventilation will decrease in the lobe subjected to volume reduction, which will be directed to the other lobes (22). The number of studies on this topic is limited in the liter- ature, and endobronchial valves have been used in all these studies as the volume reducer instead of the coil; in addition, perfusion and ventilation also decreased in the targeted lobe (23-25). Valves are of importance for obtaining these results, which are indicated in GoLD 2020 as proven among the bron- choscopic lung volume reduction procedures as an older procedure that has been the focus of a greater
number of studies (1). As far as we know, the coil procedure has been used for volume reduction in only one study in which perfusion scintigraphy scans were taken before and after the procedure with no statistically significant change observed between the two (19).
A lack of control measurements in the patients after the procedure is the most important limitation of our study. There are no post-procedure control data, especially for body plethysmography, DLCo, and the 6-minute walk test. The primary reason for this is that all patients are stage 4 advanced CoPD patients. As part of the polyclinic notes, it was noted that they are in another hospital in regard to control or inflamma- tion, or they are unable to come for control due to socioeconomic reasons, or that they have been unable to adapt to these tests, which require intensive physical effort.
In conclusion, a statistically significant improvement was observed in the PFT parameters and quality of life questionnaires following the coil procedure, which is a bronchoscopic lung volume reduction procedure.
Ethical Committee Approval: The approval for this study was obtained from Pamukkale University Ethical Committee (Decision no: 5 Date: 03.03.2020).
CONFLICT of INTEREST
The authors of this study declare that they have no conflict of interest.
AUTHORSHIP CONTRIBUTIONS Concept/Design: EU
Analysis/Interpretation: EU, NÇ, Ny, Data Acquisition: NÇ, Ny, İHA, Hş, FSş Writting: EU, NÇ, Ny, ÜA, Hş
Critical Revision: EU, NÇ, Ny, ÜA, GA
Final Approval: EU, NÇ, Ny, ÜA, İHA, Hş, FSş, GA
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